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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
321

Estudo sobre as respostas inflamatórias em modelo experimental de artrite séptica induzida por Staphylococcus aureus e suas vesículas / Study of inflammatory responses in experimental staphylococcal septic arthritis model induced by Staphylococcus aureus and extracellular vesicles

Fatima, Farah 06 March 2018 (has links)
A artrite séptica (AS), também chamada de artrite infecciosa, é uma doença inflamatória das articulações iniciada por um agente infeccioso. O agente causal mais comum da SA é Staphylococcus aureus (S. aureus). A patogênese da SA inclui uma resposta inflamatória complexa envolvendo sistema imune inato e adaptativo. As citocinas liberadas a partir de macrófagos, tais como TNF-?, IL-1? e IL-6, foram classicamente apontadas como os principais mediadores da inflamação grave que precede a destruição da cartilagem e osso e a disfunção articular permanente mediante a AS. A evidência radiológica está frequentemente presente, mas não diferencia o afrouxamento mecânico do septo das articulações. Portanto, se houver algum indício de suspeita de infecção, deve ser aspirado para avaliação microbiológica. Recentemente, as tecnologias de imagem como a micro tomografia computadorizada (?CT) foram amplamente utilizadas para modelos pré-clínicos de distúrbios articulares auto-imunes. No entanto, as características radiológicas da AS em camundongos ainda são amplamente desconhecidas. No estudo atual, os camundongos NMRI foram inoculados intravenosamente ou intra-articularmente com a cepas de S. aureus Newman ou LS-1. Os sinais radiológicos e clínicos da artrite séptica foram acompanhados durante 10 dias usando ?CT. Avaliamos as correlações entre alterações radiológicas conjuntas e sinais clínicos, alterações histológicas e níveis séricos de citocinas. Nos dias 5-7 após a infecção intravenosa, a destruição óssea verificada por ?CT tornou-se evidente na maioria das articulações infectadas. Os sinais radiológicos de destruição óssea eram dependentes da dose bacteriana. O local mais comumente afetado pela artrite séptica foi o fêmur distal nos joelhos. A destruição óssea detectada pelo ?CT foi correlacionada positivamente com alterações histológicas na artrite séptica local e hematogênica. Os níveis séricos de IL-6 foram significativamente correlacionados com a gravidade da destruição das articulações. Coletivamente, nossos dados mostram que o ?CT é um método sensível para monitorar a progressão da doença e determinar a gravidade da destruição óssea em um modelo de artrite séptica do mouse; enquanto que a IL-6 é um potencial biomarcador de destruição óssea na artrite séptica. / Extracellular vesicles (EVs) are heterogeneous population of nano- and micro-sized vesicles secreted from almost every cell type. The process of EV secretion seems to be evolutionary conserved across the species kingdoms, ranging from simple prokaryotes to higher eukaryotes including bacteria, viruses, and parasitic protozoa such as leishmania and malarial parasites, fungi, plants and animals. Recent data suggests that Staphylococcus aureus (S. aureus) bacteria secretes EVs that could mediate host-pathogen interactions. EVs have been investigated in various bacterial species which modulate the secretion of immunoregulatory molecules such as cytokines and may have key role in infection. However, their role in S. aureus septic arthritis has not been explored yet. In current study, we postulate novel perspectives for the implementation of S. aureus-derived EVs in vitro as well as in vivo model of septic arthritis. EVs derived from S. aureus were applied to stimulate mice splenocytes in vitro as well as intra-articularly and the cytokine levels were measured. Our results showed that S. aureus derived EVs potentially provoke the production of proinflammatory cytokines. TNF-?, and IL-6 were significantly elevated in splenocytes in vitro after EV-based stimulation. Moreover, NMRI mice were injected with variable doses of EVs intraarticularly and mice were observed for 10 days to examine inflammation and development of septic arthritis. Bone and cartilage destruction was assessed by histochemistry analysis to score the joint erosion. Altogether, our results demonstrate the putative role of S. aureus-derived EVs in provoking inflammation and immunological responses suggesting that these vesicles could induce and disseminate systemic immune response during the development of septic arthritis.
322

Funktionale Bedeutung der homöostatischen Chemokinrezeptoren CCR7 und CXCR5 im Verlauf von mukosalen Immunantworten

Winter, Susann 16 May 2011 (has links)
Die kontinuierliche Rezirkulation von Immunzellen durch periphere und sekundäre lymphatische Organe (SLOs) ist Bestandteil der Immunüberwachung und wichtig für die Aufrechterhaltung und Funktionsbereitschaft des Immunsystems. Der homöostatische Chemokinrezeptor CCR7 vermittelt dabei nicht nur die Rezirkulation von Lymphozyten durch SLOs, sondern scheint auch an der homöostatischen Rezirkulation von Lymphozyten durch nicht-lymphoide periphere Gewebe beteiligt zu sein. Im Rahmen dieser Arbeit wurde mithilfe von CCR7-defizienten Mäusen die funktionale Bedeutung von CCR7 für die homöostatische Rezirkulation von Lymphozyten durch das Peritoneum untersucht und nachgewiesen, dass CCR7 der dominante Chemokinrezeptor ist, der unter physiologischen Bedingungen die Transitzeit von Lymphozyten durch das Peritoneum festlegt. Die gestörte Rezirkulation von Lymphozyten begünstigte außerdem die Entstehung von tertiären lymphoiden Organen (TLOs) in der Magenschleimhaut von CCR7-defizienten Mäusen. Untersuchungen zur zellulären und molekularen Grundlage dieser und weiterer pathomorphologischer Veränderungen in der Magenschleimhaut von CCR7-defizienten Mäusen verdeutlichten die Funktion von CCR7 für die Etablierung von zentraler und peripherer Toleranz gegenüber gastrischen Antigenen. Fehlt CCR7, dann entwickelten Mäuse eine spontane Autoimmungastritis, welche durch gastritogene CD4+ T-Zellen verursacht wurde, deren Aktivierung auch unabhängig von Lymphknoten und TLOs erfolgte. Die Entstehung von TLOs wird auch bei einer durch Helicobacter pylori ausgelösten chronischen Gastritis beobachtet. Die Expression des homöostatischen Chemokinrezeptors CXCR5 und seines Liganden CXCL13 ist mit der Entwicklung dieser TLOs korreliert worden. Unter Verwendung eines Mausmodells für H. pylori-induzierte chronische Gastritis konnte gezeigt werden, dass CXCR5 die Ausbildung von TLOs vermittelt und eine Rolle für die Induktion von H. pylori-spezifischen T-Zell- sowie humoralen Immunantworten spielt. / Homeostatic recirculation of immune cells through peripheral and secondary lympoid organs (SLOs) is required for immune surveillance and the maintenance and functionality of the immune system. The homeostatic chemokine receptor CCR7 controls not only lymphoid cell trafficking to and within SLOs, but also seems to be involved in the homeostatic recirculation of lymphocytes through non-lymphoid peripheral tissues. Within the scope of this work we investigated the functional relevance of CCR7 for the homeostatic recirculation of lymphocytes through the peritoneal cavity and could show, that CCR7 is the dominant chemokine receptor which defines the transit time of lymphocytes in the peritoneal cavity under physiological conditions. Impaired recirculation of lymphocytes also promoted the development of tertiary lymphoid organs (TLOs) in the gastric mucosa of CCR7-deficient mice. Analysis of the cellular and molecular mechanisms underlying these and other pathomorphological alterations in the gastric mucosa of CCR7-deficient mice provided further evidence regarding the function of CCR7 for the establishment of central and peripheral tolerance towards gastric antigens. Mice that lack CCR7 spontaneously developed autoimmune gastritis, which was caused by gastritogenic CD4+ T-cells. Such autoreactive T cell responses were also initiated in the absence of lymph nodes and TLOs in CCR7/LT-alpha double-deficient mice. Development of TLOs is also observed during chronic gastritis induced by Helicobacter pylori. The expression of the homeostatic chemokine receptor CXCR5 and its ligand CXCL13 has been correlated with the development of these TLOs. Using a mouse model for H. pylori-induced chronic gastritis, we could show that CXCR5 is responsible for the development of TLOs and also plays a role for the induction of H. pylori-specific T and B cell responses.
323

Analyse prognostischer Faktoren für die TNFα Antagonisten-Therapie bei Rheumatoider Arthritis / Analysis of TNF-a antagonist drug response in rheumatoid arthritis by serum proteomic profiling

Rinke, Kathinka 28 March 2011 (has links)
No description available.
324

Étude de la fonction anti-apoptotique de la sous-unité R1 de la ribonucléotide réductase des virus de l’herpès simplex

Dufour, Florent 08 1900 (has links)
L’élimination des cellules infectées par apoptose constitue un mécanisme de défense antivirale. Les virus de l’herpès simplex (HSV) de type 1 et 2 encodent des facteurs qui inhibent l’apoptose induite par la réponse antivirale. La sous-unité R1 de la ribonucléotide réductase d’HSV-2 (ICP10) possède une fonction anti-apoptotique qui protège les cellules épithéliales de l’apoptose induite par les récepteurs de mort en agissant en amont ou au niveau de l’activation de la procaspase-8. Puisqu’une infection avec un mutant HSV-1 déficient pour la R1 diminue la résistance des cellules infectées vis à vis du TNFα, il a été suggéré que la R1 d’HSV-1 (ICP6) pourrait posséder une fonction anti-apoptotique. Le but principal de cette thèse est d’étudier le mécanisme et le potentiel de la fonction anti-apoptotique de la R1 d’HSV-1 et de la R1 d'HSV-2. Dans une première étude, nous avons investigué le mécanisme de la fonction anti-apoptotique de la R1 d’HSV en utilisant le TNFα et le FasL, deux inducteurs des récepteurs de mort impliqués dans la réponse immune anti-HSV. Cette étude a permis d’obtenir trois principaux résultats concernant la fonction anti-apoptotique de la R1 d’HSV. Premièrement, la R1 d’HSV-1 inhibe l’apoptose induite par le TNFα et par le FasL aussi efficacement que la R1 d’HSV-2. Deuxièmement, la R1 d’HSV-1 est essentielle à l’inhibition de l’apoptose induite par le FasL. Troisièmement, la R1 d’HSV interagit constitutivement avec la procaspase-8 d’une manière qui inhibe la dimérisation et donc l’activation de la caspase-8. Ces résultats suggèrent qu’en plus d’inhiber l’apoptose induite par les récepteurs de mort la R1 d’HSV peut prévenir l’activation de la caspase-8 induite par d’autres stimuli pro-apoptotiques. Les ARN double-brins (ARNdb) constituant un intermédiaire de la transcription du génome des HSV et activant l’apoptose par une voie dépendante de la caspase-8, nous avons testé dans une seconde étude l’impact de la R1 d’HSV sur l’apoptose induite par l’acide polyriboinosinique : polyribocytidylique (poly(I:C)), un analogue synthétique des ARNdb. Ces travaux ont montré qu’une infection avec les HSV protège les cellules épithéliales de l’apoptose induite par le poly(I:C). La R1 d’HSV-1 joue un rôle majeur dans l’inhibition de l’activation de la caspase-8 induite par le poly(I:C). La R1 d’HSV interagit non seulement avec la procaspase-8 mais aussi avec RIP1 (receptor interacting protein 1). En interagissant avec RIP1, la R1 d’HSV-2 inhibe l’interaction entre RIP1 et TRIF (Toll/interleukine-1 receptor-domain-containing adapter-inducing interferon β), l’adaptateur du Toll-like receptor 3 qui est un détecteur d’ARNdb , laquelle est essentielle pour signaler l’apoptose induite par le poly(I:C) extracellulaire et la surexpression de TRIF. Ces travaux démontrent la capacité de la R1 d’HSV à inhiber l’apoptose induite par divers stimuli et ils ont permis de déterminer le mécanisme de l’activité anti-apoptotique de la R1 d’HSV. Très tôt durant l’infection, cFLIP, un inhibiteur cellulaire de la caspase-8, est dégradé alors que la R1 d’HSV s’accumule de manière concomitante. En interagissant avec la procapsase-8 et RIP1, la R1 d’HSV se comporte comme un inhibiteur viral de l’activation de la procaspase-8 inhibant l’apoptose induite par les récepteurs de mort et les détecteurs aux ARNdb. / Elimination of infected cells by apoptosis constitutes an ancestral mechanism of host defense against viral infection. Herpes simplex viruses (HSVs) encode several viral factors to counteract the apoptotic antiviral response. Among them, the R1 subunit of HSV type-2 ribonucleotide reductase (HSV-2 R1, also named ICP10), protects cells by interrupting death receptor-mediated signaling at, or upstream of, caspase-8 activation. Since protection against tumor necrosis factor alpha (TNFα)-induced apoptosis is decreased un cells infected with an HSV type-1 R1 null mutant, it has been proposed that HSV-1 R1 (ICP6) could also possess an antiapoptotic activity. The fundamental goal of this thesis is to better understand the mechanism and the potential of the HSV R1s antiapoptotic activity. In a first study, we investigated the mechanism of the antiapoptotic activity of HSV R1s by using TNFα and Fas ligand (FasL), two death-receptor inducers involved in anti-HSVs immune response. From this work, we report three main findings on the antiapoptotic activity of HSV R1s. First, HSV-1 R1 like HSV-2 R1 has the ability to protect cells against TNFα- and FasL-induced apoptosis. Second, HSV-1 R1 contributes in protecting infected cells against FasL. Third, HSV R1s and procaspase-8 interact in a way that inhibits the dimerization/activation of caspase-8. These results suggest that in addition to counteracting death receptor-induced apoptosis, HSV R1s could inhibit apoptosis induced by other signals that trigger caspase-8 activation during HSV infection. Double-stranded RNA (dsRNA) are viral intermediates notably produced by HSVs and have been shown to induce apoptosis via caspase-8 activation. We tested in a second study whether HSV R1s have the ability to counteract apoptosis triggered by polyriboinosinic : polyribocytidylic acid (poly(I:C)), a synthetic analog of dsRNA that triggers caspase-8 activation. We showed that HSVs infection protect epithelial cells from apoptosis induced by poly(I:C). We established that HSV-1 R1 is essential for the protection of HSV-1-infected cells against poly(I:C)-induced caspase-8 activation. HSV R1s interact not only with procaspase-8 but also with the receptor interacting protein 1 (RIP1). The interaction between RIP1 and HSV-2 R1 inhibits the binding of RIP1 to the Toll/interleukine-1 receptor-domain-containing adapter-inducing interferon β (TRIF), the adaptor of Toll-like receptor 3 that is an extracellular dsRNA sensor, which is required to activate caspase-8 following extracellular poly(I:C) stimulation and TRIF overexpression. Thus, HSV R1s have the ability to inhibit poly(I:C)-induced apoptosis at several levels by preventing caspase-8 dimerization/activation and TRIF RIP1 interaction. This work sheds light on the ability of HSV R1s to manipulate apoptosis. Early during the lytic cycle, protein levels of the cellular inhibitors of caspase-8 as cFLIP drop but HSV R1s accumulate concomitantly and act as a viral inhibitor of apoptosis by binding to procaspase-8 and RIP1 in a way that impairs caspase-8 activation by death-receptors and dsRNA detectors stimulation.
325

Funktionelle Charakterisierung von CD16+ Monozytensubpopulationen

Kraus, Stephan Georg 19 October 2011 (has links) (PDF)
Seit 20 Jahren unterteilt man Monozyten in eine klassische CD14++/CD16-Population und eine proinflammatorische CD16+ Population. Letztere macht 10-20 % der peripheren Blutmonozyten aus und ist unter verschiedenen pathologischen Zuständen drastisch erhöht. Seit Kurzem wird die CD16+ Fraktion in zwei weitere Untergruppen aufgeteilt, die CD14++/CD16+ und die CD14+/CD16+ Monozyten. In der hier vorliegenden Arbeit wurde versucht, die relativ neue und wenig charakterisierte Subpopulation der CD14++/CD16+ Monozyten näher zu beschreiben. Es sollte die Frage beantwortet werden, ob diese sich von den übrigen Subpopulationen abzugrenzen lässt und damit als eigenständige Zellgruppe anzusehen ist. Die von gesunden Spendern gewonnen peripheren mononukleären Blutzellen (PBMCs) wurden mithilfe einer Magnetsäulenvorseparation von einem Großteil der T-, B- und NK-Zellen befreit. Die restlichen Zellen wurden mit Anti-CD14-FITC und Anti-CD16-PE markiert. In einem Hochgeschwindigkeitssortierer wurden diese, anhand ihres Fluoreszenzmusters, in die drei Subpopulationen CD14++/CD16- (Sub1), CD14++/CD16+ (Sub2) und CD14+/CD16+ (Sub3) aufgeteilt. Durch dieses Verfahren konnte ein hoher Reinheitsgrad erreicht werden. Die erhaltenen Subpopulationen wurden mit heterologen CD4+ T-Lymphozyten zusammen gebracht. Die Reaktion dieser T-Zellen auf die verschiedenen Subpopulationen wurde im Proliferations- und Sekretionsassay (IFN-γ, IL-4) studiert. Des Weiteren wurde die Zytokinsekretion der Monozytenarten nach definierter Stimulierung (LPS, Zymosan, aktivierte T-Zellen) analysiert. In einem zweiten Versuchskomplex wurden aus den jeweiligen Subpopulationen unreife dendritische Zellen (Sub-DCs) differenziert und diese auf bestimmte Oberflächenmarker bzw. deren Verhalten mit heterologen CD4+ T-Zellen im Proliferations-/Sekretionsassay (IFN-γ, IL-4) untersucht. Nach 7 Tagen Inkubation fanden sich im Sub2- und Sub3-Ansatz ca. 10 % mehr proliferierende T-Zellen als im Sub1-Ansatz. Dabei lag der Anteil der CD25+ T-Zellen in diesen beiden Versuchsansätzen ebenfalls um 10 % höher. Der Proliferationsassay über 14 Tage zeigte für die Sub3 ca. 10-15 % mehr proliferierende T-Zellen als für die anderen Populationen. Das Niveau der CD25-Expression der T-Zellen war hierbei in allen drei Ansätzen gleich. Im Sekretionsassay induzierten alle drei Subpopulationen eine Th1-Antwort, jedoch mit einem leicht höheren Anteil IFN-γ-positiver T-Zellen für die CD16+ Monozyten. Durch LPS-Gabe produzierten die CD14+/CD16+ Monozyten am meisten TNF-α, gefolgt von den CD14++/CD16+. Bei den CD14++/CD16- fanden sich die geringsten Mengen an TNF-α. Zusammen mit aktivierten T-Zellen demonstrierten die CD14++/CD16+ Monozyten die stärkste TNF-α-Sekretion unter allen anderen Subpopulationen. Für die beiden CD16+ Populationen wurden nach LPS-Stimulation höhere Werte für IL-1β bestimmt als für die klassischen Monozyten. Sowohl im LPS- als auch im Zymosanansatz lag die IL-6-Sekretion der CD14++/CD16- Subpopulation über der der anderen zwei Fraktionen. Unter allen drei Stimuli wurden die höchsten Werte für IL-8 bei den CD14++/CD16- Monozyten detektiert, gefolgt von den CD14++/CD16+. Am niedrigsten lag die IL-8-Produktion bei den CD14+/CD16+. Die IL-10-Sekretion im LPS- und im Zymosanansatz der CD14++/CD16- und CD14++/CD16+ Monozyten war gegenüber der CD14+/CD16+ Subpopulation erhöht. Nach Entwicklung der unreifen dendritischen Zellen aus den entsprechenden Monozytenarten weisen diese eine differenzierte Morphologie auf. Die DCs der CD14+/CD16+ Monozyten hatten eine stärkere HLA-DR-Expression in der mittleren Fluoreszenzintensität als die anderen beiden Sub-DC-Populationen, wobei sich keine Unterschiede in der HLA-DRExpressionsintensität zwischen Sub1- und Sub2-DCs feststellen ließen. Der Anteil der CD11c positiven Zellen war bei den Sub1-DCs deutlich größer als bei den Sub2-DCs. Dagegen exprimierten die Sub3-DCs praktisch kein CD11c. Im Proliferationsassay über 7 Tage ergaben sich keine signifikanten Differenzen zwischen den Subpopulationen. Allerdings zeigte sich eine Tendenz zu geringeren Werten im Anteil proliferierender bzw. CD25-positiver T-Lymphozyten für den Sub2-DC-Ansatz. Nach 14 Tagen im Assay war der Anteil der proliferierenden T-Zellen bei den Sub1-DCs um 10 % höher als bei den Sub2-DCs. Es fanden sich ca. 10 % mehr CD25+ T-Zellen im Sub1-DC-Ansatz als in den anderen beiden Ansätzen. Der Sekretionsassay erbrachte für alle Sub-DCs eine Th1-Induktion der T-Zellen. Dabei ließen sich keine Abweichungen im Anteil IFN-γ-positiver T-Zellen zwischen den einzelnen Sub-DC-Kulturen nachweisen. Die gewonnen Ergebnisse dieser Arbeit verdeutlichen auf der einen Seite das proinflammatorische Potential (z.B. TNF-α-Sekretion, erhöhte Proliferation), auf der anderen Seite die antiinflammatorische Komponente (IL-10-Sekretion) der CD14++/CD16+ Monozyten. Eine Rolle in der Regulation von entzündlichen und infektiologischen Erkrankungen erscheint für diese Subpopulation denkbar. Die Subpopulation 2 kann dabei als eigenständige Monozytenfraktion betrachtet werden. Die funktionellen Unterschiede zwischen den analysierten Monozytensubpopulationen zeigten sich auch nach deren Differenzierung zu unreifen dendritischen Zellen. In Anbetracht des erhöhten Anteils der CD16+ Monozyten im Rahmen diverser autoimmuner Krankheiten und der immer klarer werdenden Unterteilung in eine CD14++/CD16+ und eine CD14+/CD16+ Subpopulation, sollten weitere Untersuchungen zur klinischen Relevanz dieser Monozytengruppen durchgeführt werden. Die in der vorliegenden Arbeit erzielten Ergebnisse könnten bei der Zuordnung und Interpretation in diese zukünftigen klinischen Befunde behilflich sein. / For more than 20 years monocytes were subdivided in the classical CD14++/CD16- population and the proinflammatory CD16+ populations. The latter one includes about 10-20 % of the peripheral blood monocytes and is dramatically expanded under different pathological circumstances. Recently, the CD16+ fraction was further subdivided into two subpopulations: The CD14++/CD16+ and CD14+/CD16+ monocytes. In the present paper, the subpopulation of CD14++/CD16+ monocytes was characterized in order to answer the question if this subset can be distinguished as an independent cell population. T cells, B cells and NK cells were depleted from peripheral mononuclear blood cells (PBMCs) from healthy donors using immunomagnetic cell separation. Subsequently, the pre-separated cells were stained with anti-CD14-FITC and anti-CD16-PE and separated by fluorescence activated cell sorting (FACS) in three subpopulations: The CD14++/CD16- (Sub1), the CD14++/CD16+ (Sub2) and the CD14+/CD16+ (Sub3). The achieved purity was sufficient for the subsequent experiments. The obtained subpopulations were co-cultured together with heterologous CD4+ T lymphocytes. The reaction of these T cells to the different subpopulations was studied in the proliferation and secretion assay (IFN-γ, IL-4). Furthermore, the cytokine secretion of the monocyte subsets after defined stimulation (LPS, Zymosan, activated T cells) was analysed. In a second set of experiments, immature dendritic cells were differentiated from the monocyte subpopulations (Sub-DCs) and phenotypically and functionally characterized according to the expression of cell surface markers and the response to heterologous CD4+ T cells in the proliferation/secretion assay (IFN-γ, IL-4). After 7 days of incubation, the Sub2 and Sub3 of the monocytes induced approximately 10 % higher proliferation rates of T cells than the Sub1. The resulting frequency of CD25+ T cells in these two co-culture settings was also 10 % higher. The proliferation analysis after 14 days again showed for the Sub3 ca. 10-15 % more proliferating T cells than for the other populations. At this, the frequency of CD25 expression was equal in all co-cultures. In the secretion assay all three subpopulations induced a Th1 response, but the range of IFN-γ-positive T cells was somewhat higher for the CD16+ monocytes. Under LPS stimulation the CD14+/CD16+ monocytes produced the highest amounts of TNF-α followed by the CD14++/CD16+. The CD14++/CD16- showed the lowest amounts of TNF-α. In co-culture with activated T cells the CD14++/CD16+ monocytes demonstrated the strongest TNF-α secretion from all subpopulations. After LPS stimulation, a higher level of IL-1β was measured for both CD16+ populations than for the classical monocytes. In the LPS and the Zymosan stimulated cultures, the IL-6 secretion of the CD14++/CD16- subpopulation was higher than in the two other fractions. Under all three stimuli the highest levels of IL-8 were detected for the CD14++/CD16- monocytes followed by the CD14++/CD16+. The lowest IL-8 production was found by the CD14+/CD16+. The IL-10 secretion of the CD14++/CD16- and CD14++/CD16+ monocytes was increased compared to the CD14+/CD16+ subpopulation after LPS and Zymosan stimulation. The in vitro generated immature dendritic cells from the different monocyte subsets showed a differentiated morphology. The DCs of the CD14+/CD16+ monocytes had the strongest HLA-DR expression compared to the other two Sub-DC populations. No differences in the HLA-DR intensity were found between the Sub1- and Sub2-DCs. The rate of CD11c-positive cells was significantly higher in the Sub1-DCs than in the Sub2-DCs. However, the Sub3-DCs expressed no CD11c altogether. The proliferation assay over 7 days showed no significant differences between the subpopulations. Nevertheless, a tendency for lower levels of proliferating or CD25-positive T lymphocytes was seen in T cells co-cultured with the Sub2-DC. After 14 days, the ratio of proliferating T cells was 10 % higher with the Sub1-DCs than with the Sub2-DCs. The Sub1-DC co-culture yielded ca. 10 % more CD25+ T cells than the other two. The secretion assay revealed for all Sub-DCs a Th1 response of the T cells, with no differences in the amount of IFN-γ-positive T cells between the Sub-DC cultures. The results illustrate on one hand the proinflammatory potential (e.g. TNF-α secretion, higher proliferation), on the other hand the antiinflammatory effect (IL-10 secretion) of CD14++/CD16+ monocytes. A role in the regulation of inflammatory and infectious diseases seems to be possible for this subpopulation. The subpopulation 2 can be regarded as an independent fraction of monocytes. The functional differences between the analyzed monocyte subpopulations are further underscored following differentiation into immature dendritic cells. Considering the increased proportion of CD16+ monocytes in various autoimmune diseases and their clear subdivision in a CD14++/CD16+ and a CD14+/CD16+ subpopulation, new investigations about the clinical relevance are warranted. The findings obtained in the work presented could be in the basis for these future clinical studies.
326

Etude microfluidique de la rigidité leucocytaire liée au syndrome de détresse respiratoire aigue (SDRA)

Preira, Pascal 30 May 2012 (has links)
Le Syndrome de Détresse Respiratoire Aiguë (SDRA) est une maladie inflammatoire courante en service de réanimation qui touche environ 10% des patients. Une augmentation pathologique de la rigidité et/ou de l'adhésion des leucocytes des patients atteints du SDRA semble être un des facteurs déclenchants majeurs de la maladie. Nous avons utilisé la microfluidique pour mimer le passage des cellules dans les capillaires pulmonaires. L'observation du passage de cellules modèles (lignée monocytaire humaine THP-1) dans des constrictions microfluidiques (H=12µm et W=6µm) a permis de mesurer leur temps d'entrée. Ensuite nous avons incubé des cellules dans des sérums issus de malades et étudié leurs caractéristiques de passage dans des constrictions microfluidiques en fonction du temps d'incubation et de la concentration en sérum. Ces résultats sont ensuite comparés à la composition des sérums en cytokines (IL-1β, IL-6, IL-8, IL-10, IL-17, TNF-α, TGF-β et INF-γ). Des corrélations entre l'IL-8, IL-1β, le TNF-α et le temps d'entrée ont été trouvés. Ces deux cytokines peuvent jouer un rôle dans la rigidité cellulaire lors de cette maladie. En incubant ainsi nos cellules avec les recombinants humains (IL-8, IL-1β et Tnf-α), nous avons constaté une augmentation de la rigidité des cellules. D'un point de vue médical nous avons montré que l'utilisation d'anticorps bloquants anti IL-8, anti IL-1β et anti TNF-α permet de protéger les cellules. / The project consists in using microfluidic devices to test human leukocyte behavior in microcirculation. Adult Respiratory Distress Syndrome (ARDS) is a disease that affects numerous patients in intense care services with a rate of death 50%. It is triggered to the sequestration of neutrophils within the lung microvasculature. There is neither diagnostic nor efficient treatment now. We study the properties of the passage of THP-1, and real neutrophils in micro-channels of width 6µm. In order to improve the understanding of SDRA, we also incubate models cells in patient's serums who are suffering from ARDS and diagnostic tools are being developed in collaboration with the hospitals of Marseille.
327

Efeitos da adi??o da vibra??o de todo o corpo ao exerc?cio em cadeia cin?tica fechada (agachamento) sobre par?metros inflamat?rios e neuroend?crinos e a sua associa??o com o desempenho e a capacidade funcional em idosos com osteoartrite de joelho

Sim?o, Adriano Prado 22 November 2013 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2014-12-17T14:07:27Z No. of bitstreams: 2 adriano_prado_simao.pdf: 14603272 bytes, checksum: 6a0e234b9d484325125c4f251d688d0b (MD5) license_rdf: 22974 bytes, checksum: 99c771d9f0b9c46790009b9874d49253 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2014-12-17T14:08:37Z (GMT) No. of bitstreams: 2 adriano_prado_simao.pdf: 14603272 bytes, checksum: 6a0e234b9d484325125c4f251d688d0b (MD5) license_rdf: 22974 bytes, checksum: 99c771d9f0b9c46790009b9874d49253 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2014-12-17T14:08:31Z (GMT) No. of bitstreams: 2 adriano_prado_simao.pdf: 14603272 bytes, checksum: 6a0e234b9d484325125c4f251d688d0b (MD5) license_rdf: 22974 bytes, checksum: 99c771d9f0b9c46790009b9874d49253 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2014-12-17T14:09:21Z (GMT) No. of bitstreams: 2 adriano_prado_simao.pdf: 14603272 bytes, checksum: 6a0e234b9d484325125c4f251d688d0b (MD5) license_rdf: 22974 bytes, checksum: 99c771d9f0b9c46790009b9874d49253 (MD5) / Made available in DSpace on 2014-12-17T14:09:21Z (GMT). No. of bitstreams: 2 adriano_prado_simao.pdf: 14603272 bytes, checksum: 6a0e234b9d484325125c4f251d688d0b (MD5) license_rdf: 22974 bytes, checksum: 99c771d9f0b9c46790009b9874d49253 (MD5) Previous issue date: 2013 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (Capes) / Funda??o de Amparo ? Pesquisa do estado de Minas Gerais (FAPEMIG) / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Introdu??o: Recentemente, a vibra??o de todo o corpo (VTC) tem sido um m?todo de exerc?cio f?sico indicado para aumentar o desempenho e a capacidade f?sico-funcional de idosos com osteoartrite (OA) de joelho. No entanto, os mecanismos relacionados aos efeitos produzidos por essa modalidade ainda n?o foram completamente investigados. Objetivos: O objetivo deste estudo foi investigar os efeitos da adi??o de VTC aos exerc?cios de agachamento na concentra??o plasm?tica de marcadores inflamat?rios e no desempenho e capacidade funcionais de idosos com OA de joelho na fase remissiva da doen?a (Estudo 1) e investigar os efeitos da adi??o do treinamento de VTC ao exerc?cio de agachamento em mulheres idosas com OA de joelho na fase remissiva da doen?a nos seguintes par?metros: 1) for?a isom?trica do m?sculo quadr?ceps; 2) concentra??o plasm?tica de BDNF; e 3) na concentra??o salivar da raz?o testosterona/cortisol (Estudo 2). Investigar a rela??o entre os n?veis plasm?ticos e no l?quido sinovial do TNF-? e seus receptores sol?veis (sTNFR1 e sTNFR2) assim como de BDNF em idosos com OA de joelho e ainda verificar a rela??o destes com a gravidade da OA e o autorrelato de dor, rigidez e fun??o f?sica com o WOMAC (Western Ontario and McMaster University Osteoarthritis Index) em idosos com OA de joelho na fase inflamat?ria aguda (Estudo 3). Metodologia: No estudo 1, trinta e dois idosos com OA de joelho foram divididos em tr?s grupos: grupo que realizou exerc?cio de agachamento associado a plataforma vibrat?ria (grupo plataforma N=11), grupo que realizou exerc?cio de agachamento sem vibra??o (grupo agachamento N=10) e o grupo controle (N=11). Um programa estruturado de exerc?cios de agachamento foi executado tr?s vezes por semana em dias alternados por doze semanas nos grupos plataforma e agachamento. A concentra??o plasm?tica de receptores sol?veis de TNF-? (sTNFR1 e sTNFR2) foi analisada usando a t?cnica de ELISA. O WOMAC foi usado para avaliar o autorrelato da fun??o f?sica, dor e rigidez. O teste de caminhada de 6 minutos, a escala de Berg e o teste de velocidade da marcha foram utilizados para avaliar a fun??o f?sica. No estudo 2, foram selecionadas quinze mulheres idosas com idade maior ou igual a 60 anos que tinham sido diagnosticadas com OA em pelo menos um joelho. A interven??o consistiu de doze semanas seguidas de exerc?cios de agachamento, 3 vezes por semana. O protocolo de exerc?cio foi similar em ambos os grupos diferindo apenas da presen?a de vibra??o. J? no estudo 3 participaram vinte e sete idosos diagnosticados com osteoartrite de joelho e dezenove idosos saud?veis. Radiografias ?ntero-posteriores do joelho foram realizadas para determinar a gravidade da doen?a no joelho afetado. A classifica??o radiogr?fica da OA do joelho foi realizada utilizando os crit?rios Kellgren-Lawrence. Os n?veis de TNF-?, sTNFR1, sTNFR2 e BDNF no plasma e no l?quido sinovial foram determinados por ELISA. Resultados: No estudo 1, o grupo que realizou exerc?cios de agachamento na plataforma vibrat?ria mostrou diminui??o nas concentra??es plasm?ticas dos marcadores inflamat?rios sTNFR1 e sTNFR2 (p<0,001 e p<0,05, respectivamente), no autorrelato da dor (p<0,05), melhora no equil?brio (p<0,05) e na velocidade e dist?ncia caminhada (p<0,05 e p<0,001, respectivamente) comparado com o grupo controle. O teste de velocidade da marcha tamb?m apresentou aumento no grupo plataforma quando comparado ao grupo agachamento (p<0,01). Os resultados do estudo 2 demonstraram uma varia??o (?) positiva dos valores da for?a isom?trica muscular do quadr?ceps (p=0,02) e da concentra??o plasm?tica de BDNF (p=0,03) no grupo vibra??o ap?s o per?odo de interven??o. A varia??o (?) na raz?o testosterona/cortisol (T/C) n?o diferiu significativamente, entre os grupos (p=0,61). No estudo 3, os n?veis de BDNF no l?quido sinovial correlacionou-se significativamente com dor autorrelatada [WOMAC] (rs = 0,39, p=0,04). Com rela??o aos receptores sol?veis para TNF-?, observou-se uma diferen?a entre os n?veis de sTNFR1 e de sTNFR2, tanto no plasma quanto no l?quido sinovial em pacientes com OA do joelho (1091 ? 99,48 pg / mL versus 2249 ? 126,3 pg / mL e 2587 ? 66,12 pg / mL versus 2021 ? 107,0 pg / mL, respectivamente). Al?m disso, os n?veis de sTNFR1 no l?quido sinovial foram, negativamente, correlacionadas com a dor e a fun??o f?sica autorrelatada (rs -0,6785, p<0,0001 e rs -0,4194; p=0,03, respectivamente). Ao passo que, os n?veis de sTNFR2 no l?quido sinovial foram negativamente correlacionadas com dor e rigidez articular (rs -0,5433, p=0,01 e rs -0,4249; p=0,02, respectivamente). Conclus?es: Os resultados dos estudos supracitados indicam que a adi??o da vibra??o de todo o corpo ao treinamento com exerc?cio de agachamento, nas condi??es experimentais propostas, melhora o equil?brio est?tico e din?mico e o desempenho da marcha e ao mesmo tempo reduz a autopercep??o de dor e a concentra??o de marcadores inflamat?rios (sTNFR1 e sTNFR2) em idosos com OA de joelho na fase de remiss?o da doen?a. Al?m disso, a associa??o da vibra??o de todo o corpo ao exerc?cio de agachamento promove uma melhora na for?a muscular de membros inferiores em mulheres idosas com OA de joelho na fase de remiss?o da doen?a e proporciona uma resposta adaptativa na concentra??o de BDNF sem altera??o na rela??o muscular de anabolismo/catabolismo. J? os resultados da rela??o entre sist?mico e local, indicam que os n?veis de BDNF sist?micos est?o associados com o mecanismo da dor articular na OA de joelho. Com rela??o aos receptores sol?veis de TNF-?, evidenciou-se a presen?a de receptores sol?veis para TNF-? no l?quido sinovial de pacientes com OA prim?ria de joelho e a rela??o destes receptores com par?metros cl?nicos. / Tese (Doutorado) ? Programa Multic?ntrico de P?s-Gradua??o em Ci?ncias Fisiol?gicas, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2013. / ABSTRACT Introduction: Recently, whole body vibration (WBV) has been an alternative method of exercise that has been indicated to improve the physical performance of the elderly with osteoarthritis (OA) knee. However, the mechanisms related to the effects produced by this training mode have not been fully elucidated in the literature. Objectives: 1) To investigate the effects of the adittion of whole-body vibration to squat exercises on the plasma concentration of inflammatory markers and the functional performance of elderly individuals with knee OA remission phase (Study 1) and investigate the effects of WBV in addition to squat exercise training in elderly women with knee OA remission phase on the following parameters: 1) isometric strength of the quadriceps muscle; 2) BDNF plasma concentration; and 3) the testosterone/cortisol salivary concentration ratio (Study 2). 3). To analyze the concentrations of TNF-?, soluble receptors (sTNFR1 and sTNFR2) and BDNF in both plasma and synovial fluid of patients with inflammatory acute phase primary knee osteoarthritis during inflammatory acute phase, and to determine the possible correlations of plasma and synovial fluid TNF-?, soluble receptors (sTNFR1 and sTNFR2) and BDNF with the radiographic grading of knee OA and with self-reported pain, stiffness and physical function (Study 3). Methods: In study 1 thirty-two elderly subjects with knee osteoarthritis were divided into three groups [i.e., squat exercises on a vibratory platform (platform group N= 11), squat exercises without vibration (squat group N= 10) and the control group (N=11)]. The structured program of squat exercises in the platform and squat groups was conducted three times per week, on alternate days, for twelve weeks. The plasma concentration of TNF-? soluble receptors (sTNFR1 and sTNFR2) were analyzed using ELISA. The Western Ontario and McMaster University Osteoarthritis Index (WOMAC) questionnaire were used to evaluate self-reported physical function, pain and stiffness. The 6-minute walk test, the Berg balance scale, and gait speed were used to evaluate physical function. In study 2 the eligible patients were fifteen (15) elderly women ? 60 years of age who had been diagnosed with OA in at least one knee. The intervention consisted of uninterrupted squatting exercises for twelve weeks, 3x/week. The exercise protocol was similar in both groups differing only in the presence of vibration. In study 3 samples of plasma taken from the peripheral blood and of synovial fluid taken from the knee of patients with osteoarthritis (OA) were collected (n=27). Anteroposterior knee radiographs were taken to determine disease severity in the affected knee. Radiographic grading of OA in the knee was performed using the Kellgren-Lawrence criteria. Furthermore, plasma was collected from the peripheral blood of 19 healthy individuals, with no radiographic change in the hips and knees. The Western Ontario and McMaster University Osteoarthritis Index (WOMAC) questionnaire was used to evaluate self-reported physical function, pain and stiffness. ELISA measured the TNF-?, sTNFR1, sTNFR2 and BDNF levels in the plasma and synovial fluid. Results: In the study 1 the group that performed squat exercises on a vibratory platform, there were significant differences in plasma concentrations of the inflammatory markers sTNFR1 and sTNFR2 (p<0.001 and p<0.05, respectively), self-reported pain (p<0.05), balance (p<0.05) and speed and distance walked (p<0.05 and p<0.001, respectively) compared with the control group. The gait speed test also showed significant differences between the squat and platform groups (p<0.01). In the results of the study 2, the VG group demonstrated a significantly greater change (?) in IQMS values (p = 0.02) and in BDNF plasma concentrations (p = 0.03) after the intervention period compared with the EG group. The change (?) in T/C ratio showed no difference between the groups (p = 0.61). In the results of the study 3, the plasma BDNF levels significantly correlated with self-reported pain [WOMAC] (rs=0.39, p=0.04). According to soluble receptors to TNF-?, there was a difference between sTNFR1 and sTNFR2 levels in plasma as well as in synovial fluid in patients with knee (1091 ? 99,48 pg / mL versus 2249 ? 126,3 pg / mL e 2587 ? 66,12 pg / mL versus 2021 ? 107,0 pg / mL, respectively). Synovial fluid sTNFR1 levels were negatively correlated with pain and physical function self-reported (rs-0.6785, p<0.0001 and rs-0.4194, p=0.03, respectively). Synovial fluid sTNFR2 levels were negatively correlated with pain and joint stiffness (rs-0.5433, p=0.01 and rs-0.4249, p=0.02, respectively). Conclusions: The results of the above studies indicate that the addition of vibration training the whole body to squat exercise in the experimental conditions resulted in improvement in static and dynamic balance and gait performance and reduced the self-perception of pain and the concentration of inflammatory markers (sTNFR1 and sTNFR2) in elderly patients with knee OA. We also demonstrate that the combination of vibration training the whole body to squat exercise can promote an improvement in lower limb muscle strength in elderly women with knee OA and still provide an adaptive response to the concentration of BDNF compared with no change in muscle anabolism/catabolism. The results of the relationship between systemic and local concentration indicate that the systemic BDNF levels are associated with the mechanism of joint pain in knee OA. With respect to TNF-? soluble receptors, the findings demonstrated the presence of soluble receptors for TNF-alpha, particularly sTNFR1, in the synovial fluid of patients with primary knee OA and the relationship between these receptors and clinical parameters.
328

Efeito de drogas sintéticas inibidoras do fator de necrose tumoral alfa na artrite reumatoide em ratos / Effect of synthethic drugs inhibiting tumor necrosis factor alpha on the experimental arthritis in rats

Mariana Trivilin Mendes 23 August 2017 (has links)
A artrite reumatoide (AR) é uma doença autoimune, inflamatória, crônica, sistêmica e de etiologia desconhecida que pode ser induzida experimentalmente em animais por administração de colágeno e adjuvante (CIA). Os medicamentos biológicos contra o fator de necrose tumoral (TNF)-&alpha; são indicações terapêuticas atualmente consolidadas para os casos mais severos de AR. As limitações ao uso dessa classe de medicamentos têm sido o alto custo e a dificuldade em fabricar genéricos ou similares com composição, qualidade e desempenho equivalentes na mesma dose e via de administração. O presente estudo avaliou a hipótese de que drogas sintéticas que inibam a produção de TNF-&alpha; e / ou fatores relacionados teriam potencial para tornarem-se terapias complementares ou alternativas eficientes para esta doença. Para isso, foram utilizados ratos submetidos ao modelo CIA e tratados cronicamente com pentoxifilina (PTX), rolipram (ROL), talidomida (TAL) e rupatadina (RUP). Um tratamento com prednisolona (PRED) foi também efetuado para avaliar sua influência na eventual ação antiartrítica de PTX, ROL, TAL e RUP, de modo a mimetizar seu efeito imunossupressor, quando administrada agudamente (AG) antes de medicamentos biológicos, bem como pelo seu conhecido efeito anti-inflamatório, quando administrada cronicamente (CR) no tratamento da AR. O desenvolvimento da AR e a efetividade dessas drogas sobre a AR foram avaliadas, de forma seletiva e sequencial, por meio da detecção de eritema e cianose, bem como medidas de edema, massa corporal, hemograma, TNF-&alpha; no plasma, fator reumatoide (FR) e anticorpo antinuclear (ANA) no soro, interleucina (IL)-1&beta; e IL-6 no soro e líquido sinovial, atividade de aminopeptidase básica (APB) na fração solúvel (FS) do tecido sinovial (TS) e de células mononucleares do sangue periférico (PBMCs), densitometria óssea e análise histológica. A hepatotoxicidade dessas drogas foi avaliada pelas medidas de alanina-transaminase (ALT) e aspartato-transaminase (AST) no plasma. A AR caracterizou-se pelo aumento de TNF-&alpha; plasmático e de IL-1&beta; e IL-6 no líquido sinovial, alterações histológicas na articulação tíbio-tarsal, bem como edema, cianose, eritema, diminuição de linfócitos e atividade APB de FS aumentada no TS e diminuída em PBMCs. A AR aumentou ALT e AST. O tratamento com PRED crônico promoveu um efeito antiedematogênico. O coquetel (MIX de PTX+ROL+RUP+TAL) também apresentou efeito antiedematogênico. A administração concomitante de PRED AG ou PRED CR com MIX não produziu sinergismo ou potenciação do efeito antiedematogênico da administração isolada do MIX ou da PRED crônica. Além do MIX, ROL e TAL diminuíram o edema. MIX, ROL e TAL melhoraram TNF-&alpha; no plasma e APB na FS do TS e não causaram hepatotoxicidade, tal como refletido nos níveis de ALT e AST. TAL recuperou ALT e AST, sem alteração do hemograma. Uma vez que PTX e RUP não apresentaram efeito antiedematogênico, ROL e TAL foram hipotetizados como os prováveis responsáveis pela atividade antiartrítica do MIX. Então, os tratamentos com ROL, TAL e ROL+TAL foram selecionados para avaliação da histologia óssea e medidas de parâmetros diferenciais entre animais controles sadios e artríticos. Esta avaliação mostrou que o tratamento isolado da AR com ROL ou TAL não alterou IL-6, mas recuperou IL-1&beta; no líquido sinovial, efeitos esses que não se diferenciaram do tratamento combinado de ROL+TAL, exceto pelo fato de que essa combinação também diminuiu a massa corporal. TAL se destacou por seu efeito hepatoprotetor nos animais AR. Considerando os efeitos conhecidos de RUP, PTX, TAL e ROL é possível hipotetizar que a ação antiartrítica de TAL e ROL deve-se à inibição da síntese de TNF-&alpha; decorrente da inibição de PDE4 em suas principais fontes celulares. Os dados deste estudo prospectivo fornecem subsídios adicionais que estimulam a realização de novos ensaios clínicos, mais amplos e sistematizados, sobre os efeitos antiartríticos de ROL e TAL. Conclui-se que o uso isolado de TAL emerge como uma alternativa terapêutica econômica, simples e eficaz para a AR, enquanto a combinação de ROL+TAL pode ser uma opção viável para portadores de AR com sobrepeso ou obesidade / Rheumatoid arthritis (RA) is an autoimmune, inflammatory, chronic and systemic disease with unknown etiology that can be experimentally induced in animals by administration of collagen and adjuvant (CIA). Biological drugs against tumor necrosis factor (TNF)- &alpha; are therapeutic indications currently consolidated for the most severe cases of RA. The limitations for the use of this class of drugs have been the high cost and the difficulty to manufacture a generic or similar ones with equivalent composition, quality and performance under the same dosage and route of administration. The present study evaluated the hypothesis that synthetic drugs that inhibit the production of TNF-&alpha; and/or related factors would have potential to become efficient complementary or alternative therapies for this disease. For this purpose, male rats submitted to the CIA model were chronically treated with pentoxifylline (PTX), rolipram (ROL), thalidomide (TAL) and rupatadine (RUP). The treatment with prednisolone (PRED) was also performed to evaluate its influence on the possible antiarthritic action of PTX, ROL, TAL and RUP, in order to mimic its immunosuppressive effect when acutely (AG) administered prior to biological drugs, as well as due to its known anti-inflammatory effect when administered chronically (CR) to treat RA. The development of RA and the efficacy of these drugs on RA were evaluated, by selective and sequential ways, through the detection of erythema and cyanosis, as well as measurements of edema, body mass, hemogram, plasma TNF-&alpha;, rheumatoid factor (FR) and anti-nuclear antibody (ANA) in serum, interleukin (IL)-1&beta; and IL-6 in serum and synovial fluid, basic aminopeptidase activity (APB) in soluble fraction (FS) from synovial tissue (TS) and from peripheral blood mononuclear cells (PBMCs), bone densitometry and histological analysis. The hepatotoxicity of these drugs was evaluated by measurements of alanine-transaminase (ALT) and aspartate-transaminase (AST). RA was characterized by increased TNF-&alpha; in plasma and IL-1&beta; and IL-6 in synovial fluid, histological alterations in the tibio-tarsal joint, as well as edema, cyanosis, erythema, decreased lymphocyte number and increased APB activity in TS and decreased APB activity in PBMCs. RA produced increased ALT and AST. As expected, the chronic treatment with PRED promoted an antiedematogenic effect. The cocktail (MIX of PTX+ROL+RUP+TAL) also presented antiedematogenic effect. Concomitant administration of acute or chronic PRED with MIX did not produce synergism or potentiation of the antiedematogenic effect due to the single administration of MIX or chronic PRED. In addition to MIX, ROL and TAL were also antiedematogenic. MIX, ROL and TAL ameliorated plasma TNF-&alpha; and APB in FS from TS without hepatotoxicity, as reflected by ALT and AST levels. TAL recovered ALT and AST, but it did not affect the hemogram. Since PTX and RUP did not present antiedematogenic effects, ROL and TAL were hypothesized as probable responsible for the antiarthritic activity of MIX. Thus, the treatments with ROL, TAL and ROL+TAL were selected for evaluation of bone histology and measurements of differential parameters between healthy control and arthritic animals. This evaluation showed that the treatment of RA with ROL or TAL alone did not alter IL-6 levels, but recovered IL-1&beta; in the synovial fluid. Both these effects were not different from those of the concomitant treatment with ROL+TAL, except that this combination also decreases the body mass. TAL stands out for its hepatoprotective effect in RA animals. Considering the known effects of RUP, PTX, TAL and ROL it can be hypothesized that antiarthritic action of TAL and ROL is due to the inhibition of TNF-&alpha; synthesis as consequence of its inhibition in its main cellular sources by PDE4. Data from this prospective study provide additional subsidies that stimulate further and more comprehensive clinical trials on the antiarthritic effects of ROL and TAL. In conclusion, the treatment with TAL alone emerges as an economical, simple and effective therapeutical alternative for RA, while the combination of ROL+TAL can be a viable option for RA sufferers with overweight or obesity
329

Expressão de genes da resposta imune em bovinos infestados com carrapatos (Boophilus microplus)

Belo, Vanessa de Almeida 15 February 2008 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-10-14T12:30:34Z No. of bitstreams: 1 vanessadealmeidabelo.pdf: 412659 bytes, checksum: 2be0607436379c3a9ca0f2415972f9be (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-10-22T13:05:05Z (GMT) No. of bitstreams: 1 vanessadealmeidabelo.pdf: 412659 bytes, checksum: 2be0607436379c3a9ca0f2415972f9be (MD5) / Made available in DSpace on 2016-10-22T13:05:05Z (GMT). No. of bitstreams: 1 vanessadealmeidabelo.pdf: 412659 bytes, checksum: 2be0607436379c3a9ca0f2415972f9be (MD5) Previous issue date: 2008-02-15 / Nos países tropicais, as perdas causadas pela infestação de carrapatos em bovinos acarretam um grande impacto no sistema de produção animal. Recentes estudos têm mostrado a importância de fatores genéticos ligados a resistência a carrapato em Bos taurus indicus e Bos taurus taurus e que as citocinas têm um papel crítico na prevenção ou progressão de doenças. O objetivo desse trabalho foi avaliar os níveis de expressão dos genes IL-10 e IL-4 relacionados ao perfil imunológico Th2 associado à susceptibilidade ao carrapato e os genes IL-2 e IFN- relacionados ao perfil imunológico Th1 associado à resistência ao parasito. Além destes genes, analisou-se o perfil de expressão do gene TLR-2, importante no processo de reconhecimento de patógenos e os genes IL-8 e TNF-α importantes no processo inflamatório inicial. Seis animais mais resistentes e seis animais mais susceptíveis de uma população F2 de 332 animais, originária do cruzamento de animais F1(½ Holandês: ½ Gir), foram selecionados baseado na contagem de carrapatos e valor genético. Amostras de tecido foram coletadas de pele no 5° e 12° dias após a infestação para extração de RNA total. As PCRs em tempo real foram realizadas usando o gene GAPDH como controle endógeno. Os animais resistentes e susceptíveis apresentaram aumento de expressão do gene IL-10 no 5° (p<0,01) e 12 ° dias após a infestação (p<0,05). O gene IL-2, nos animais resistentes e susceptíveis, no 5° dia após a infestação não apresentou alteração da expressão sendo que 12° dia, em ambos os grupos de animais, este gene passou a ser mais expresso em relação ao animal controle sugerindo um perfil de resposta imunológica do tipo de Th2 nos animais resistentes e susceptíveis nos primeiros dias após a infestação. O gene IL-4 apresentou uma tendência ao aumento de expressão nos animais resistentes e susceptíveis em relação ao controle, sendo o perfil Th2 sugerido atribuído a IL-10 produzida por linfócitos T regulatórios (p>0,05). O gene TNF- apresentou aumento de expressão nos animais susceptíveis no 5° dia após a infestação com posterior diminuição no 12° dia após a infestação (p<0,05). Nos animais resistentes não foi observada alteração da expressão deste gene, isto sugere que ele possa estar mais atuante no início do processo inflamatório, logo após a fixação do carrapato. A mesma observação estende-se para o gene IL-8, em que não foi verificada alteração de expressão nos animais resistentes, embora nos animais susceptíveis este gene apresentou diminuição da expressão no 12° dia após a infestação (p<0,05). Quanto ao gene IFN-, não houve diferença de expressão entre os animais resistentes e susceptíveis, sendo que este gene parece não estar relacionado ao mecanismo de resistência. O gene TLR-2 apresentou diminuição da expressão em ambos os grupos de animais. Estes resultados sugerem que a resposta imune adquirida avaliada neste trabalho não apresenta papel preponderante no mecanismo de resistência e que resposta imune inata poderia está envolvida no mecanismo de resistência ao carrapato. Portanto, avaliação da resposta imunológica horas após a fixação do carrapato poderia nos fornecer resultados mais conclusivos. / In tropical countries losses caused by tick infestation in cattle lead to a major impact on animal production systems. Recent studies have shown the importance of genetic factors linked to tick resistance in Bos indicus and Bos taurus as well as the critical role in the prevention or progression of diseases mediated by cytokines. The aim of this work was to evaluate gene expression of IL-10 and IL-4 in relation to tick susceptibility associated with the Th2 profile and gene expression of IL-2 and IFN- in relation to tick resistance associated with the Th1 profile. In addition, the expression of TLR-2, important in the process the recognition of pathogens, and TNF-α and IL-8 genes, important in the initial inflammatory process, were evaluated. Six tick-resistant and six tick-susceptible animals from a F2 population of 332 animals, originated from the cross of F1 animals (½ Holstein: ½ Gir), were selected based on tick count and breeding value for tick resistance. Skin biopsies were collected in the 5th and 12th days after tick infestation. The GAPDH was used as endogenous control to normalize the amount of starting cDNA target in the real-time PCR assay. Both resistant and susceptible animals showed increased gene expression of IL-10 in the 5th and 12th days after infestation in relation to control animal (p<0.05). The IL-2 gene showed no change of expression in the 5th day after infestation for the resistant and susceptible animals. In the 12th post infestation, both resistant and susceptible animals showed increased gene expression in relation to control animal. These results suggest an enhancement of Th2 profile through the increase of IL-10 mRNA levels and a possible inhibition of the Th1 pattern in both groups (resistant and susceptible) starting 5 days after infestation and return to normal by day 12. Despite our results suggest the occurrence of the Th2 profile, the susceptible and resistant animals did not show variation on gene expression for IL-4 in relation to control animal. The susceptible animals showed increased expression of TNF-α in the 5th day after infestation. However, in the 12th day post infestation it was noted a decrease in the gene expression level. The resistant animals showed no change in the expression of this gene in relation to control animals suggesting that TNF-α could be more actively expressed in the early steps of the inflammatory process. Similarly, the resistant animals showed no variation in the expression of IL-8 while the susceptible animals showed increased expression in the 12th day post infestation. There were no differences of expression between resistant and susceptible animals in relation to IFN-γ what suggests that this gene might not be involved in the resistance mechanism. The TLR-2 gene showed decreased expression in both resistant and susceptible animals (p<0.05). Finally, there was no difference in expression between susceptible and resistant animals in relation to all selected genes in the 5th and 12th days after infestation. These results suggest that the acquired immunity evaluated in this work might not have preponderant role in the resistance mechanism. The innate immunity might be playing a major role in the bovine tick resistance/susceptibility mechanism in early hours after infestation.
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Avaliação da aterosclerose subclínica em portadores de HDL-colesterol marcadamente elevado / Evaluation of subclinical atherosclerosis in individuals with markedly elevated HDL-cholesterol

Antonio Gabriele Laurinavicius 28 March 2016 (has links)
O HDL-c é um fator de risco cardiovascular negativo e sua concentração plasmática apresenta relação inversa com a incidência de eventos cardiovasculares. Entretanto, as evidências relativas ao grupo de indivíduos com níveis de HDL-c acima do percentil 95 da população geral ainda são escassas e o impacto da hiperalfalipoproteinemia (HALP) sobre o risco cardiovascular continua representando motivo de controvérsia na literatura médica. Alguns estudos em populações específicas associam a HALP a aumento do risco cardiovascular. Ao mesmo tempo, outros estudos identificaram populações de indivíduos hipoalfalipoproteinêmicos com marcada longevidade. Assim, demonstrou-se aparente dissociação entre níveis de HDL-c e risco cardiovascular em determinadas populações, reconduzível a aspectos disfuncionais da HDL. O objetivo do presente estudo foi verificar o papel da HALP na determinação do risco cardiovascular; comparar a prevalência de doença cardiovascular subclínica, avaliada por meio da quantificação ultrassonográfica da Espessura Íntimo-Medial Carotídea (EIMC), entre portadores de HDL-c >= 90mg/dL (grupo HALP) e portadores de concentrações de HDL-c atualmente consideradas normais (entre 40 e 50mg/dL para os homens e entre 50 e 60mg/dL para as mulheres); e avaliar características e função da HDL em portadores de HALP por meio do estudo de sua composição, de sua capacidade de efluxo de colesterol, e de sua atividade anti-inflamatória e antioxidante, correlacionando estas características com a presença de doença cardiovascular subclínica avaliada por meio da determinação da EIMC, da Velocidade de Onda de Pulso (VOP) e da presença de Calcificação Arterial Coronariana (CAC) avaliada pela TCMD. Para responder estas perguntas, o presente estudo foi articulado em dois braços: Braço 1: Análise da coorte do estudo ELSA com o objetivo de determinar a prevalência de HALP em uma população geral; definir o perfil demográfico, antropométrico e metabólico dos portadores de HALP; e comparar a prevalência de doença vascular subclínica deste grupo com controles da mesma coorte com níveis normais de HDL-colesterol. Braço 2: Recrutamento de 80 voluntários hígidos e portadores de HALP para avaliação da correlação entre presença de doença vascular subclínica, e aspectos estruturais e funcionais da HDL. Em seus dois braços, o estudo levou a quatro conclusões principais: 1) Níveis marcadamente elevados de HDL-c estão associados a menor espessura íntimo-medial carotídea quando comparados a níveis de HDL-c considerados normais pelas diretrizes vigentes. Embora portadores do fenótipo HALP apresentem, como grupo, um perfil metabólico mais favorável que o encontrado em indivíduos com HDL-c normal, a associação entre EIMC e HALP foi independente dos fatores de risco tradicionais, indicando que a menor prevalência destes últimos em portadores de HDL-c marcadamente elevado justifica apenas parcialmente a menor prevalência de doença vascular subclínica neste grupo; 2) Embora a HALP se apresente como um fenótipo ateroprotetor, há indivíduos com níveis marcadamente elevados de HDL-c que evoluem com doença cardiovascular, clínica ou subclínica. Neste contexto, nossos resultados indicam correlação entre os três métodos avaliados para estudar doença vascular subclínica em portadores de HALP: EIMC, VOP e CAC; 3) Os fatores de risco tradicionais continuam exercendo seu peso na determinação do risco cardiovascular em portadores de HALP. Idade, tabagismo, hipertensão arterial, hipertrigliceridemia e altos níveis de LDL-c apresentaram associação estatisticamente significativa com a presença de doença vascular subclínica no grupo estudado; 4) A avaliação da composição e da função da HDL em portadores de HALP pode permitir identificar indivíduos especificamente mais suscetíveis à aterosclerose. Nossos resultados indicam que, em particular, a atividade anti-inflamatória da HDL, avaliada pela capacidade de inibição da produção de IL-6; o efluxo de colesterol e a capacidade de transferência de triglicérides apresentaram associação independente com menor espessura íntimo-medial carotídea em portadores de HALP, enquanto níveis mais altos de Apo A-IV se associaram a maior grau de doença cardiovascular subclínica / HDL-c is a negative cardiovascular risk factor and its plasma concentration is inversely related to the incidence of cardiovascular events. However, evidence of benefit among subjects with HDL-c levels above the 95th percentile of the general population is still scarce and the impact of hyperalphalipoproteinemia (HALP) on cardiovascular risk continues to represent matter of debate in the medical literature. Some studies with specific populations indicated an increased cardiovascular risk associated with HALP. In addition, other reports identified groups of patients with marked hypoalphalipoproteinemia and longevity. Hence, there could be a dissociation between HDL-c levels and cardiovascular risk in certain populations, possibly due to dysfunctional HDL particles. The aim of this study was to investigate the role of HALP phenotype in determining cardiovascular risk; to compare the prevalence of subclinical cardiovascular disease, assessed by ultrasound measurement of Carotid Intima-Media Thickness (CIMT) among patients with HDL-c >= 90mg/dL (HALP group) and patients with HDL-c currently considered normal (40-50mg/dL for men and 50-60mg/dL for women); and to evaluate HDL functionality in patients with HALP through the study of its composition, its cholesterol efflux capacity, and its anti-inflammatory and antioxidant activity; correlating those characteristics with the presence of subclinical cardiovascular disease assessed by CIMT, Pulse Wave Velocity (PWV) and Coronary Artery Calcification (CAC). To answer these questions, the present study was articulated into two arms: Arm 1: ELSA-Brasil study cohort analysis in order to assess HALP prevalence in a general population, defining demographic, anthropometric and metabolic profile of HALP individuals; and comparing the prevalence of subclinical vascular disease among HALP subjects with controls with normal HDL-c. Arm 2: Recruitment of 80 healthy volunteers with HALP to study the correlation between subclinical vascular disease and HDL functionality in this group. Our study led to four main conclusions: 1) markedly elevated HDL-c is associated with lower CIMT compared to the control group with normal HDL-c levels. Although individuals with HALP display a more favorable metabolic profile than subjects with normal HDL-c, the association between CIMT and HALP was independent of traditional risk factors, indicating that the lower prevalence of subclinical vascular disease in this group is only partially justified by the lower prevalence of cardiovascular risk factors; 2) Although HALP can be regarded as an atheroprotective phenotype, there are individuals with markedly elevated levels of HDL-c who develop cardiovascular disease. Our results indicate good correlation of the three methods here adopted to study subclinical vascular disease among HALP patients: CIMT, VOP and CAC; 3) Traditional risk factors continue to exert their weight in determining cardiovascular risk in patients with HALP. Age, smoking, hypertension, hypertriglyceridemia and high levels of LDL-c were significantly associated with the presence of subclinical vascular disease among HALP individuals; 4) the assessment of the HDL composition and functionality in patients with HALP may allow to identify individuals specifically more susceptible to atherosclerosis. Our results indicate that, in particular, cholesterol efflux capacity, the anti-inflammatory activity of HDL, and triglyceride transfer capacity were independently associated with lower CIMT in HALP individuals, while higher levels of Apo A-IV were associated with a greater burden of subclinical cardiovascular disease

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